This chapter is from the book

This chapter is from the book

If you don't have access to a SQL database such as MySQL or Oracle, you
will almost certainly have a DBM-style database system available to you. DBM
stands for database manager and DBM-like systems allow you to store and
manipulate name/value pairs on your system.

DBA stands for Database abstraction layer, and these functions are designed
to provide a common interface to a range of file-based database systems.

Although DBA functions do not offer you the power of a SQL database, they are
flexible and easy to use. The fact that DBA functions stand above a range of
common database systems, means that your code is likely to be portable even if
the database files themselves might not be.

In this hour, you will learn:

How to open a database

How to add data to the database

How to extract data from the database

How to change and delete items

How to store more complex kinds of data in DBM-style databases

Beneath the Abstraction

In order to use the DBA functions, you need to have one of the supported
database systems installed. If you are running Linux, it is likely that you will
have GDBM (the GNU Database Manager installed). For each system there
is a corresponding compile option which should have been used when PHP was
installed. You can see the supported databases and their corresponding compile
options in Table 11.1.

If your system and PHP installation supports one of these
systems you will be able to use the DBA functions with no problems. Note that
support for the cdbm system (which is designed for fast access to static
databases) is read-only.